The present invention broadly relates to athletic footwear and, more specifically, pertains to a new and improved construction of a ski boot.
Generally speaking, the ski boot of the invention comprises a shell member, a rear upper portion hinged on an axis transverse to the longitudinal axis of the ski boot, and an instep pressure pad or restraining member arranged within the ski boot acting on the upper portion of the user's foot and adjustable by means of a tensioning mechanism or device mounted on the exterior of the heel portion of the boot.
In ski boots with an exterior shell of rigid material in which the foot is inserted from the side or through an aperture in the front portion of the shell, it is known to urge the heel of the foot downwards and towards the rear of the ski boot by means of an instep pressure or retaining device. Significant in this regard are U.S. Pat. Nos. 3,529,368 and 3,599,351. This instep pressure device comprises straps which run over the instep of the foot and whose tension is adjustable, for instance, by means of a buckle connection or a tensioning lever which is mounted on the exterior of the boot.
Such known pressure devices are inconvenient to use and do not permit the user to readily and quickly put on or remove the boot. These known solutions are furthermore not suitable for ski boots which have a rear upper portion mounted in hinged fashion upon the basic shell member.
Ski boots of the latter type are known from the international patent application published as No. WO79/00770 and from U.S. Pat. No. 4,160,332 corresponding to German Pat. Publication No. 27.12.001. These references teach a restraining element running over the instep of the foot and connected to a tensioning mechanism accessible from the exterior of the boot or mounted on the exterior of the rear upper portion of the boot. The tensioning mechanism or the connection between the restraining device and the tensioning mechanism in such known types of ski boot is, however, so arranged that any angular motion of the rear upper portion is directly transmitted to the pressure pad. The result of this coupling is that changes in the angular position of the rear upper portion of the boot change the retaining force exerted on the foot. Bending the lower leg forward results in a forward rotation of the rear upper portion and increases the retention force acting on the foot. Similarly, leaning the lower leg to the rear causes a reduction of this retention force.
This change of the restraining or holding force acting on the foot with each change in the angular position of the lower leg is undesirable since when leaning forward the pressure pad may exert an excessive pressure on the middle region of the foot and when leaning backwards the pressure pad may not exert sufficient force to retain the foot properly within the boot.
When walking longer distances the wearer of the type of boot described above often releases the rear upper portion in order to give the lower leg a greater degree of freedom or even to make it possible to stand in an upright position. Releasing the rear upper portion in this manner is equivalent to rotating it backwards which results in a loosening of the pressure pad for the reasons given above. This means that the foot is no longer adequately retained by the pressure pad and can therefore move within the shell member of the boot which also makes walking difficult.
Other constructions of ski boots are known from U.S. Pat. Nos. 3,530,594 and 3,747,235 and French Pat. No. 2,045,321.